Comparison

Incredible Numbers! vs Rectangles & Primes

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Incredible Numbers!

Explore the hidden beauty of mathematics with interactive examples and puzzles. Discover concepts like infinity, Pi, and prime numbers through engaging articles and demonstrations crafted by a renowned professor. Uncover the mathematical patterns in nature, music, and codes.

Highlights
  • 23 articles by Professor Ian Stewart
  • 71 interactive demonstrations
  • 15 mathematical puzzles
  • Topics: Infinity, Pi, Music, Codes, Nature, Primes, Polygons, Factorials
  • Interactive examples and simulations
  • Focus on the beauty of mathematics
Features
Read full description

Selected by Apple as Best of 2014, and winner of the 2015 Digital Book Award for Best Nonfiction App. Bestselling author Professor Ian Stewart is your guide through Incredible Numbers. Numbers define the patterns of sunflowers; they bring pleasure through music; and they help us answer existential questions like; ‘How many ways are there to lace my shoes?’ Interactive examples – from simple equations to a working Enigma machine – put the beautiful concepts behind mathematics at your fingertips. “A measure of Ian Stewart’s success is that he’s able to give a clear path through some very hairy mathematics.” – Times Higher Education Supplement There’s so much more than a few screenshots can show: – 23 articles crafted by Prof. Ian Stewart, embedded with 71 groundbreaking interactive demonstrations. – 23 bespoke interactive sections that let you immerse yourself in the beautiful patterns and concepts behind each topic. – 15 of Ian Stewart’s famous mathematical puzzles. Topics include: • Infinity – Explore infinity and understand what it really means to say something is infinite. • Pi – Unwrap the mysteries of pi to see why this strange number is so important and why it’s not just about circles. • Music – Music and math share the beauty of finding patterns in complexity. Detailed interactives show you how they relate in real, meaningful and fun ways. • Codes – See how the power of numbers can unlock complexity in codes. • Nature – See how numbers work in nature by looking at the Fibonacci sequence and how it appears in the real world in beautiful and surprising ways. • Primes – Discover the mysterious patterns in prime numbers, and why they are so important. • Polygons – Get to grips with shapes and polygons. Classical geometry is just another way to think about numbers! • Factorials – How many ways can you lace your shoes? Did you know that if you have 4 eyelets, there are 24 possible lacing styles? With 12 eyelets there are 479,001,600 possibilities. See why this is so in Factorials! Incredible Numbers aspires to convince you that maths is beautiful. Mathematicians know this already. The great solutions and proofs shine to them, but their underlying beauty has been hidden behind abstract algebra and complex equations. Until now. If you enjoy this app, don’t forget to rate it in the App Store.

About

Rectangles & Primes

Features
Read full description

Rectangle provides a fun and insightful maths experience for kids aged 6 to 12. They will improve their understanding of number factorization and prime numbers.

Screenshots

Rectangles & Primes2 screens

Verdict

The call

The clearest difference is price: Rectangles & Primes at Free against Incredible Numbers!'s $6.99. Rectangles & Primes also leads on update cadence (every 3 weeks vs every 10 months) and device support (3 vs 1). Incredible Numbers!'s advantage is iOS requirement (12.1 vs 15.0). On ads and in-app purchases there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Rectangles & Primes is free to download; Incredible Numbers! costs $6.99 up front. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

Incredible Numbers! ships an update every 10 months, Rectangles & Primes every 3 weeks. The most recent releases landed on October 19, 2026 and October 25, 2026 respectively.

Scorecard4 real differences · 6 level
Incredible Numbers! versus Rectangles & Primes: the parameters behind the verdict, then further details
ParameterIncredible Numbers!Rectangles & Primes
Price$6.99Free — better
Rating5.0 (9 ratings) — better—
Positive reviews73.1% of reviews—
Number of ratings9 — better—
Update frequencyEvery 10 monthsEvery 3 weeks — better
AdsNoNo
In-app purchasesNoNo
MonetizationPaid—
DevicesiPadiPhone, iPad, iPod — better
Requires iOS12.1 — better15.0
Further details — not scored
Size107 MB10 MB
Age rating4+4+
DeveloperNatureGuides Ltd.Johannes Charra

In-app purchases

None

Incredible Numbers!

No in-app purchases

None

Rectangles & Primes

No in-app purchases

Questions

Is Incredible Numbers! free?
Incredible Numbers! costs $6.99, with no in-app purchases.
Is Rectangles & Primes free?
Rectangles & Primes is free to download, with no in-app purchases.
Do Incredible Numbers! or Rectangles & Primes have ads?
Neither Incredible Numbers! nor Rectangles & Primes shows ads.
Which is updated more often, Incredible Numbers! or Rectangles & Primes?
Incredible Numbers! ships an update every 10 months, and Rectangles & Primes every 3 weeks. Most recently, Incredible Numbers! was updated on October 19, 2026 and Rectangles & Primes on October 25, 2026.

Other comparisons